Characterization of Wood and Wood-Plastic Composite

Abstract
Wood-plastic composites (WE) were prepared with low-grade wood (kadom, simul, and mango) of Bangladesh and MMA (methyl methacry-late) under Co-60 gamma irradiation with a 3-Mrad dose (800 krad/h). Polymer loading and tensile properties of the composites were determined and the effect of urea and N-vinyl pyrrolidone (NVP) on these properties was studied. The polymer loading (PL) increases slightly (2-3%) with the addition of urea to the MMA + MeOH solution: however, this increment is 616% with NVP addition and 12-54% with urea + NVP, depending on the type of wood. Similarly, the tensile strength (TS) increased by 11-25%, the bending strength (BS) by 31-48%, and the compressed strength (CS) by 40-67%. To further characterize the composite, the samples were investigated with infrared (IR), electron-spin resonance (ESR), and thermally simulated luminescence (TSL) techniques. IR studies reveal that MMA was grafted with the wood substrate; ESR and TSL investigations detected the residual free radicals (not the primary free radicals) in the composites.